CVE‑2025‑15556: Notepad++ WinGUP Updater Lacks Integrity Checks, Enabling Arbitrary Code Execution
What It Is — The WinGUP updater bundled with Notepad++ downloads installer code without performing any integrity verification (e.g., signature or hash check). An attacker who can intercept or redirect the update traffic could supply a malicious installer that runs with the privileges of the logged‑in user.
Exploitability — No public exploit has been observed, but a proof‑of‑concept exists and the vulnerability scores high on the CVSS scale (≥8.0).
Affected Products — Notepad++ (Windows) when the WinGUP automatic update feature is enabled.
Why It Matters for Trust & Control Assurance
- Continuous monitoring of third‑party software updates is a core control objective; a gap here weakens the audit trail for supply‑chain integrity.
- Demonstrable evidence that update mechanisms enforce integrity checks is increasingly demanded by enterprise buyers during security reviews.
- Mapping this issue to the Verisq Common Framework (VCF) highlights the “Software Integrity & Secure Configuration Management” control that spans SOC 2, ISO 27001, NIST CSF 2.0 and others.
Recommended Actions
- Disable Notepad++ auto‑update until a signed, integrity‑checked release is available.
- Apply the vendor‑issued patch or upgrade to the latest version that includes cryptographic verification of updates.
- Deploy endpoint monitoring to detect execution of unsigned binaries.
- Record the update process and any remediation steps in your control‑evidence repository for audit readiness.
Source: CISA KEV – CVE‑2025‑15556